Perhaps I read naively, but I never thought that communism was at the centre of the Culture. The Culture itself always sounded amorphous and distant; the 'black hole at its centre' more of an indication that there was no justification for how the system worked - and no need for one, as it was a great place for telling stories.
As for Ken MacLeod ... he seems to maintain a broad political church all on his own. However, most people seem to have read their own political position into the Fall Revolution, seeing how it is generally lauded by both libertarians and socialists, which makes it interesting that ESR has seen the opposite view most strongly.
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